Air Conditioners

How to Solve Water Leak from Split AC

Hot summer can be unbearable, and as much as we want to keep our homes cooler, you cannot run a water leaking split AC. Have you seen water drops inside the house near the AC or under the outdoor unit? If you have, you might have a water leak problem. The big question is, how do you solve a water leak from a split AC?

The best way to solve a water leak from your split AC is to identify the problem culprit. These four are the leading causes of split AC water leaks: clogged drain line, dirty air filters, low refrigerant level, or the AC unit mounting angle slants on the wrong side. Start by troubleshooting these parts and fix them. If the problem doesn’t go away, call an HVAC professional.

Of course, the option of calling a professional HVAC will save you the hassle of opening the AC unit and having to deal with all the troubleshooting. But it’s not a must, and you might save some cost by doing it yourself; you might even learn a thing or two. Assuming you’ve decided to try and solve the problem yourself, this post will guide you on how to solve a water leak from a split AC.

How to Solve Water Leak from a Split AC (Simple Steps)

Before you go tearing apart your split AC, understand these possible reasons why it is leaking water and how to solve the problem:

1) Dirty Air Filters

The air filters inside a split AC indoor unit trap any dirt particles and other air contaminants in the air before releasing them back to the room. Eventually, they will get clogged with all the dirt.

When the filters are clogged, they can cause hot air sucked in from the room to accumulate inside the unit and lack a way to flow out freely.

When the hot air mixes with the cold air, it triggers accelerated condensation in the wrong places, and that produces water that will ultimately drop outside the drain pan to your flooring.


The best solution is to take out these air filters and conduct a thorough cleaning using dishwasher soap and water.

Remove filters by lifting the top cover and snap or slide them out. If you’re unsure or have a problem removing them, kindly refer to your AC’s user manual, the maintenance section.

It’d be best to check the air filters for dirty every month and clean them if they need it.

2) Blocked or Clogged Drain Line

If the air filters are clean or have cleaned them and the AC is still leaking water, the blocked or clogged drain line might be causing an overflow.

As the AC cools your home, the dirt collected inside it might drop with the water and accumulate as sludge inside the drain line. As time goes by, the accumulation grows large enough to block the water flow and eventually causing a clogging.

Check the drain pipe from the outside and see if there any water dropping out. If nothing is coming out or the water drops take time to come out even when the AC is running, there is a clog.


You need a Wet/Dry Shop Vacuum to suck out the clog or the blocking dirt. You can also use a regular vacuum cleaner. However, it’ll be best to allow the dirt collection bag to dry out under the sunlight, or you can replace it with a replaceable bag if yours has it.

How do you do it? Remove the vacuum attachment and insert the AC drain pipe into the vacuum hose. Get a wet towel and wrap it around the joint to create enough suction.

Power on the vacuum cleaner for a minute or two. Allow it to suck all the dirt in the drain line. It should be able to dislodge anything clogging or blocking the drain pipe. If you feel something pass through the hose, it’s a good sign that you’ve unclogged the drain.

You can test the water flow of the drain pipe by slowly emptying a water container on the third module of the freezing coils. Be very careful not to drop water on AC’s electrical parts.

Look at the water flow as it drains out through the drain hole. It should flow as quickly as possible and empty somewhere outside of the house.

Go back to the house, wipe the AC unit, and mop your floor where the leaking water was dropping on to see if the problem is solved.

3) AC Unit Slanting the Wrong Side

Another reason your split AC is leaking water could be that the AC unit mounting has a slight angle away from the drainpipe in such a way that the water flows on the wrong side.

The angle might not be that significant, but it could be creating small water accumulation on the wrong side to the extent that it gets freezing cold and start to rise on the aluminum fins.

When that happens, the water will eventually overflow and lead to water dripping outside the drain container and your floor.


If that is what’s happening with your split AC, it’d be best to level the unit correctly. You could try putting a small stick on the mounting bracket at the top to raise the AC unit toward the drain pipe.

If there is no space to do so, you’ll have to take it down and install it properly using the installation instructions in the user manual.

4) Low refrigerant level

If your split AC’s refrigerant level is too low, the unit loses pressure, leading to freezing. There will be ice buildup on the copper coils or on the evaporator coil when that happens. As the water melts, it might overflow the drain pan quickly than the drain pipe can handle, or it might drop outside, leading to a water leak.


Get your split air conditioner serviced by a professional who can supply the refrigerant, and you can solve the water leaking problem. It’d also help make your cooler while returning the electric usage to normal.


You might need to open the main AC cover to access the interior when solving the water leak. If you need to remove the cover, run to the breaker box, locate the AC breaker and set it to the OFF position. Get a Phillips screwdriver and remove two screws on the main door.

Snap it out, and you should have full access to the drain pan and the freezing coils. Be careful not to use force and keep away from the aluminum fins.

If there is a need to clean them, use low-pressure water to spray them. You can apply some dishwasher soap if there’s too much dirt. Don’t forget to return every piece where it belongs before calling it a day.

Related Questions

Can we use split AC when water is leaking?

Of course not! You cannot use AC when water is leaking. Why? When water is leaking from your AC, it’s a sign of a problem. And depending on the type of air conditioner you have, it can lead to a whole new water-related problem such as water damage to your ceiling, indoor dampness, mold and mildew growth.

Solve Water Leak from A Split AC – Prevent Water Damage

Water dripping from your Split AC can cause floor damage or even create a dump air situation that can lead to series of water damages in your home, such as mold growth. If you notice your AC leaking water, the first step would be to try out the above solutions. If the problem doesn’t improve, get an HVAC professional to help you out.

About the author

Sharif Hasan

I am Sharif a data-driven marketer by profession and run The Spruce Air. I am very interested in keeping good-quality air inside of my home. Besides, I love to share my air-related knowledge through my website.

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